July 14, 2009

Dumb Bus, Smart Bus, Empty Bus

In Beijing it is not an uncommon sight to see a caravan of identically numbered buses arrive at a bus stop one after the other. For example, bus #31 will be immediately followed by another bus #31 and yet another bus #31. This is often followed by a very long wait until the next cluster of buses arrive.

Each bus departs their starting point at regularly scheduled intervals, say every 10 minutes. At the first stop the mass of transit users converge on the first bus and try to get on board before everyone else. The pushing and shoving lasts approximately 1-3 minutes. Traffic also moves at an Arnab's pace in Beijing. During this time, the second bus on the same route has left the bus station and is now only around 10 minutes behind. Repeat this pattern a couple of more times, and by the second or third stop on the route the two buses are together. Another one to two stops later, all three buses will be within striking distance of each other. The cycle repeats after every 3 buses since by then another huge group of riders has gathered at the bus stop.

The swarm that enters the first bus leaves it packed to the brim. People are squashed against the windows and doors. All the seats on the second bus fill up quickly, but there is room to comfortably stand for the stragglers. The third bus obligatorily stops at each designated spot, but since 95% of the passengers have already boarded one of the two previous buses that arrived in the past minute it is left mostly empty. It is difficult to predict the change in arrival times that would take place if ridership was evenly distributed amongst the three buses, but at the very least the ride would be a lot more comfortable for most people.